Q: What are the performance tradeoffs using 16 bpp color?
It depends on the application. In 16 bpp (bits per pixel) mode, the video frame buffer is twice as large as at 8 bpp. The graphics controller must pull twice as much data across the system bus from RAM, so there will be less bus bandwidth for other operations. This may "memory starve" other processes, slowing them down.
Also, some system resources (e.g. PCMCIA) require longer memory cycles. At higher panel refresh rates, these longer cycles can starve the video processor, resulting in interference on the screen when the resources are used. Typically, ADS optimizes the refresh rate of a panel so that the panel display is never interrupted.
Under some conditions, however, using a 16 bpp display mode can result in faster system operation than in 12-bit color. In 16 bpp the GDI doesn't have to map the colors in the image to the color palette. Display of video may be slower, static images may display faster than at 12 bpp.
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